Population migration to Mongol from central China reached unprecedented levels during the Kangxi, Yongzheng and Qianlong reigns. The Qing government opposed, or at best was unenthusiastic for, this spontaneous migration. As this migration steadily increased, the Qing government issued a series of orders to restrict it. Ultimately the ban on migration failed, despite the fact that the Qing dynasty was able to control the entire country tightly and effectively during this perid. Why? Through an examination of the trends in migration and the development of the government’s restrictive polices, this paper attempts to offer a reasonable explanation.